Debugger: use debug break slots to break at function exit.

src/mips/full-codegen-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_MIPS
 
 // Note on Mips implementation:
 //
@@ skipping 476 matching lines @@
     EmitProfilingCounterDecrement(weight);
     Label ok;
     __ Branch(&ok, ge, a3, Operand(zero_reg));
     __ push(v0);
     __ Call(isolate()->builtins()->InterruptCheck(),
             RelocInfo::CODE_TARGET);
     __ pop(v0);
     EmitProfilingCounterReset();
     __ bind(&ok);
 
-#ifdef DEBUG
-    // Add a label for checking the size of the code used for returning.
-    Label check_exit_codesize;
-    masm_->bind(&check_exit_codesize);
-#endif
     // Make sure that the constant pool is not emitted inside of the return
     // sequence.
     { Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm_);
       // Here we use masm_-> instead of the __ macro to avoid the code coverage
       // tool from instrumenting as we rely on the code size here.
       int32_t arg_count = info_->scope()->num_parameters() + 1;
       int32_t sp_delta = arg_count * kPointerSize;
       SetReturnPosition(function());
-      __ RecordJSReturn();
       masm_->mov(sp, fp);
       int no_frame_start = masm_->pc_offset();
       masm_->MultiPop(static_cast<RegList>(fp.bit() | ra.bit()));
       masm_->Addu(sp, sp, Operand(sp_delta));
       masm_->Jump(ra);
       info_->AddNoFrameRange(no_frame_start, masm_->pc_offset());
     }
-
-#ifdef DEBUG
-    // Check that the size of the code used for returning is large enough
-    // for the debugger's requirements.
-    DCHECK(Assembler::kJSReturnSequenceInstructions <=
-           masm_->InstructionsGeneratedSince(&check_exit_codesize));
-#endif
   }
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(Variable* var) const {
   DCHECK(var->IsStackAllocated() || var->IsContextSlot());
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(Variable* var) const {
@@ skipping 5049 matching lines @@
          reinterpret_cast<uint32_t>(
              isolate->builtins()->OsrAfterStackCheck()->entry()));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS